1. Field of the Invention
The present invention relates to a method for extending a bridge domain of an overlay SDN network, and more particularly, to a method which is capable of extending the bridge domain of the overlay SDN network to an overlay SDN network which uses another solution.
2. Description of the Related Art
An overlay SDN model which targets a server farm network is presented in software defined networking (SDN) as new network architecture.
Here, the overlay means a method for performing communication between virtual machines (VM) by encapsulating the packets by a particular protocol, regardless of the physical network configuration.
Further, the overlay SDN means a networking system which controls a virtual switch to which the virtual machines are connected so that the virtual machines can be connected to each other through a tunnel.
Meanwhile, in order to connect the overlay SDN networks which the different another solution, there has been a need to connect the gateways of each overlay SDN network through a legacy network.
That is, there has been a problem of connecting the overlay SDN network using the solution A with the overlay SDN network using the solution B necessarily through the gateway as a L3 device.
FIG. 1 is a diagram for explaining a method for connecting an overlay SDN network using the different solutions in accordance with the conventional method.
In this embodiment, the description will be given of a case where the solution used in the first overlay SDN network 100 is different from the solution used in the second overlay SDN network 200.
Since a first virtual machine 150, a second virtual machine 160, a third virtual machine 170 and a fourth virtual machine 180 belonging to the first overlay SDN network 100 belong to the same bridge domain 110, the virtual machines belonging to the first bridge domain 110 may be connected to one another through tunneling between the switches 130, 140.
For example, the first virtual machine 150 and the third virtual machine 170 may transmit and receive the packets through the tunneling between a first switch 130 connected to the first virtual machine 150 and a second switch 140 connected to the third virtual machine 170.
However, it was necessary to transmit and receive the data from and to the virtual machines belonging to the bridge domains of the overlay SDN networks different from each other, necessarily through the gateway.
For example, in order to connect the first virtual machine 150 belonging to the first bridge domain 110 with the fifth virtual machine 250 belonging to the second bridge domain 210, there was a need to connect the first gateway 300 of the first overlay SDN network 100 with the second gateway 400 of the second overlay SDN network 200 through a legacy network 500.
That is, since a bridge domain policy used in one overlay SDN network may not applied to a bridge domain of another overlay SDN network so as to connect the overlay SDN networks in which the different solutions are used, there was inconvenience which requires change of various set values.
For example, there may be a problem which requires change of the protocol used in the first overlay SDN network 100 to the protocol used in the second overlay SDN network 220.
Therefore, there is a need for a method capable of combining multiple virtual servers or physical servers included in the overlay SDN network using the different solutions by one bridge domain.